Light emitting device and lighting apparatus

Abstract

A light emitting element according to an embodiment includes a substrate; a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer which are disposed on the substrate; a reflective layer which is disposed on the light emitting structure and has first and second areas neighboring each other in a horizontal direction; a first electrode which is disposed in at least a portion of the first area of the reflective layer with passing through the second conductive semiconductor layer and the active layer and extending to the first conductive semiconductor layer; a first insulating layer disposed between the first electrode and the side of the light emitting structure and between the first electrode and the reflective layer; a diffusion barrier layer disposed in the second area of the reflective layer; a second insulating layer disposed on the first electrode and the diffusion barrier layer; and first and second bonding layers which pass through the second insulating layer and are connected to the first electrode and the diffusion barrier layer, respectively.

The invention claimed is: 
     
       1. A light emitting device, comprising:
 a substrate; 
 a light emitting structure comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer disposed on the substrate; 
 a reflective layer disposed on the light emitting structure, the reflective layer having first and second areas neighboring each other in a first direction; 
 a first electrode disposed to extend to the first conductivity type semiconductor layer and passing through the second conductivity type semiconductor layer and the active layer in a second direction crossing the first direction at a portion of the first area of the reflective layer; 
 a first insulating layer interposed between the first electrode and a side surface of the light emitting structure and between the first electrode and the reflective layer; 
 a diffusion barrier layer disposed at the second area of the reflective layer; 
 a second insulating layer disposed on the first electrode and the diffusion barrier layer; and 
 first and second bonding layers respectively connected to the first electrode and the diffusion barrier layer with passing through the second insulating layer in the second direction, 
 wherein the diffusion barrier layer is disposed between the reflective layer and the second bonding layer in the second direction. 
 
     
     
       2. The light emitting device according to  claim 1 , wherein the diffusion barrier layer and the first insulating layer are disposed on the reflective layer while being spaced apart from each other in the first direction. 
     
     
       3. The light emitting device according to  claim 1 , wherein the diffusion barrier layer and the first electrode are disposed to be spaced apart from each other in the first direction. 
     
     
       4. The light emitting device according to  claim 1 , further comprising:
 a sub-mount; and 
 first and second metal pads disposed on the sub-mount while being spaced apart from each other in the first direction, 
 wherein the first and second conductivity type semiconductor layers are connected to the first and second metal pads, respectively. 
 
     
     
       5. The light emitting device according to  claim 4 , further comprising:
 a first bump interposed between the first bonding layer and the first metal pad; and 
 a second bump interposed between the second bonding layer and the second metal pad. 
 
     
     
       6. The light emitting device according to  claim 1 , wherein the first insulating layer and the second insulating layer are made of different materials, respectively. 
     
     
       7. The light emitting device according to  claim 1 , wherein the first insulating layer and the second insulating layer are made of the same material. 
     
     
       8. The light emitting device according to  claim 1 , wherein the diffusion barrier layer has a first thickness of 50 nm to several μm in the second direction. 
     
     
       9. The light emitting device according to  claim 1 , wherein the diffusion barrier layer has a first width in the first direction at a portion thereof contacting the reflective layer at the second area such that the first width is equal to or greater than a second width in the first direction of a portion of the second bonding layer passing through the second insulating layer. 
     
     
       10. The light emitting device according to  claim 1 , wherein the diffusion barrier layer and the first electrode are made of the same material. 
     
     
       11. The light emitting device according to  claim 1 , wherein the diffusion barrier layer and the first electrode are made of different materials, respectively. 
     
     
       12. The light emitting device according to  claim 1 , wherein the diffusion barrier layer has a first thickness in the second direction of the light emitting structure such that the first thickness is greater than a second thickness of the first electrode. 
     
     
       13. The light emitting device according to  claim 1 , wherein the diffusion barrier layer may comprise at least one of Ni, Ti, Pt, or W. 
     
     
       14. The light emitting device according to  claim 1 , further comprising:
 a second electrode electrically connected to the second conductivity type semiconductor layer. 
 
     
     
       15. The light emitting device according to  claim 14 , wherein the diffusion barrier layer and the second electrode form an integrated structure. 
     
     
       16. The light emitting device according to  claim 1 , wherein the diffusion barrier layer has a circular, oval or polygonal planar shape. 
     
     
       17. The light emitting device according to  claim 1 , wherein the diffusion barrier layer is locally disposed only between the second area of the reflective layer and the second bonding layer. 
     
     
       18. The light emitting device according to  claim 1 , wherein the diffusion barrier layer, the second area of the reflective layer, and the second bonding layer are disposed to be overlapped with each other in the second direction. 
     
     
       19. A lighting apparatus comprising:
 a header; and 
 a light emitting device according to  claim 1 , the light emitting device being disposed on the header.